It has been the practice in the prior art to stamp and form electrical contacts or terminals from a continuous strip of metal. The contacts at first were individually assembled to a printed circuit board and then soldered fixedly in place. The disadvantage of such a technique involved a requirement for hand labor to sort the contacts from one another, to assemble the contacts in desired alignment within the board, and to straighten the contacts in their final desired positions after soldering the contacts in place. Because hand labor is costly, there has been considerble effort directed toward reducing the amount of hand labor required for assembly of contacts to a printed circuit board. One of the first improvements to result from such effort resided in locating the terminals serially along a common carrier strip which was formed integral with the terminals during the stamping and forming process. This permitted the carrier strip to be fed into an insertion machine which individually severed a terminal from the strip and forcibly inserted it into a printed circuit board. The prior art further evolved into a technique whereby a plurality of electrical terminals along a common carrier strip were located within a comb-type tool which aligned the plurality of terminals for simultaneous insertion within corresponding locations in a circuit board. Using this technique, insertion of a larger number of terminals were simultaneously inserted, the common carrier strip served to align the terminals while the terminals were soldered fixedly in place within the printed circuit board. Subsequently, the carrier strip was removed from the terminals, leaving the terminals individually located within the printed circuit board.
Another version of the above techniques is described in U.S. Pat. No. 3,618,207 wherein a plurality of terminals, which extend transversely from a common carrier strip, have a body of insulating material molded transversely across the contacts. This molding is done using an intermittent molding process which provides individual housings. However, the disclosed insulative material is rigid and would prevent or hinder the further step of forming the terminals into particular configurations. Also, once the metal carrier strip is removed the individual molded housings will not be in strip form. This molding operation is relatively slow and costly.
U.S. Pat. No. 3,239,798 describes a multiple contact connector in which a plurality of spaced-apart, elongated, parallel contact strips are formed from a sheet of electrically conductive material, preferably by a known etching technique. The strip is placed between two sheets of insulation material and bonded thereto along only certain predetermined lengths of the contact strips. The ends of the strips are not bonded. The ends of the strips are formed into alternate arcuately extending resilient contacts and the laminar center portion is formed into a channel. The alteration of the arcuate ends causes the non-bonded insulation material to be separated from the formed contact ends to allow electrical contact with suitable circuitry. The steps of forming the connector according to this patent are quite complex.
U.S. Pat. No. 4,245,876 discloses a continuous strip of electrical terminals which is formed by stamping rectangular openings in a strip of metal. A strip of dielectric material is then adhered to the metal strips, after which the metal strips are formed into electrical terminals of a selected configuration. Discrete lengths of the formed terminals in strip form are held together as separate terminals via the dielectric material which can be severed from the continuous strip for specified uses. This arrangement has been found to be unsatisfactory for a number of reasons. One reason is the application of an adhesive to the metal strips must be followed by pressure and heat, requiring additional equipment and time, thereby increasing the cost of production. Another reason the above solution is unsatisfactory is that the adhesive does not completely encase the metal strips. Consequently, the terminals are not precisely maintained in position. This is an unacceptable result, as only the slightest movement of the terminals will result in problems in subsequent operations. A further problem with the adhesive is that it becomes brittle after time. This causes the adhesive to break, leaving the terminals with nothing to maintain them in position. When this occurs, the terminals must be handled as individual terminals with all of the problems and costs associated therewith.